Paper pulp beating engine



Aug. 4, 1953 E. HERY Erm. 2,647,444

PAPER PULP BEATING ENGINE Filed May 25, 1948 2 Sheets-Sheet 1 Fig Aug. 4, 1953 E. HERY ETAL PAPER PULP BEATING ENGINE 2 Sheets-Sheet 2 Filed May 25. 1948 mmm Patented Aug. 4, 1953 PAPER PULP BEATING ENGINE Edouard Hry, Neuilly-sur- Seine, and Kristen Andreas Thorsen, Grenoble, France Application May 25, 1948, Serial N o. 29,158 In France May 30, 1947 3 Claims.

The present invention relates to machines for the manufacture of paper pulp and which are known as beating engines.

, AOne knows that machines of this kind comprise `a rotating drum provided with cells or grooves constituted by projecting longitudinal blades and which are filled with pulp, the said pulp being finished by the friction which takes place between the edge of the said blades which are integral with the drum cylinder and the edge of stationary blades constituting the bed-plate or bed-plates, the said grooves being emptied under the action of centrifugal force. The result of this arrangementis that the eflivciency of a beating engine depends upon the quantity of pulp which passes per unit of time between the cylinder blades and those of the bedplate. This quantity depends of course on the degree of filling for the grooves and on the number of cylinder blades that passl before the bedplate per unit time, that is to say it depends at the same time upon the density of blades on the `cylinder and on the circumferential speed of the latter. Now an increasednumber of blades on the cylinder, i. e. a reduction in the width of the grooves as well as a higher speed for the cylinder (the latter increase on account of the centrifugal force which repels the pulp) are prejudicial to the filling of the grooves, so that in practice the speed of the cylinder hardly eX- ceeds 10 to 12 meters per second while the distance across the cylinder blades which constitute the grooves is at least of 30 mm. It has already been proposed for improving the filling of the grooves to supply the cylinder with pulp through 5^ revolving paddles or propellers or through pumps, but such devices require a considerable expenditure of power to meet their function satisfactorily..

The beating engine of the invention has for its object to remedy these inconveniences and includes means providing an excellent lling of the grooves without any unproductive expenditure of power. This beating engine is characterized by the fact that it comprises a pulp container or reservoir arranged so that it delivers the pulp to the cylinder of the beating engine under a high hydrostatic pressure.

According to an embodiment of the invention, thefeeding reservoir contains some pulp Whose level is at a height positively above the axis of the cylinder, for-instance at a level situated at 1.50 to 2 meters above the axis of a cylinder having 1 m. in diameter, and this cylinder is suppliedtangentially with pulpv throughv a discharge port disposed in the lower part of the reservoir, along a cylindrical segment which is preferably small and adjustable.

The advantages of the beating engine according to the invention can be explained as follows:

On one hand the pressure applied on the pulp at the time it comes in contact with the cylinder facilitates the filling of the grooves.

On the other hand, owing to that high pressure and to the arrangement mentioned above, the pulp at the discharge port is in the most favorable conditions to flll up the grooves as completely as possible.

The result is that without prejudice to the lling of the grooves and to the expenditure in power, the circumferential speed of the cylinder can be increased to 16 to 20 meters per second approximately, while the width and depth of the grooves can be reduced, to 15 mm. by 15 mm., so that finally the eniciency of the engine is considerably increased.

As will be shown further the beating engine according to the invention may be embodied in a most simple and compact design by using the pulp thrown out of the grooves during the revolution of the cylinder for bringing up the said pulp in the reservoir to the level required to generate the desired hydrostatic pressure.

One embodiment of a beating engine with a xed'cylinder and an adjustable bed-plate for continuous production is described below by way of example and shown diagrammatically on the annexed drawing in which:

Fig. 1 is a transverse section of the said beating engine.

Fig. 2 is a top plan view of the engine shown on Fig. l, but including some modifications.

Figs. 3 and 4 give a vertical section of certain details.

The cylinder 2 with its blades is mounted on its stationary bearings in a beater vat l formed with reinforced concrete, the said cylinder rotating in the direction of arrow 3. The double movable bed-plate 4 is disposed in a block pivoted at 5 and rests on the rear of cylinder 2 on account of its own weight and of the pressure which is applied thereto by a wheel and an endless worm t operated by hand wheels 1.

The pulp is supplied in a continuous manner by a hopper 8 disposed at one end of the beating engine, to the reservoir 9 constituted by the beater vat l and by a wall l 0, the said wall being substantially higher than the cylinder 2 and having its lower part l I surrounding, at a small distance, the bottom of the front half of the cylinder 2; the said lower part Il ends at a small distance from the surrounding nose I2 of the bedplate so as to provide a free space of pump discharge port preferably provided with a control vane (not shown).

At the other end of the beating engine, the reservoir 9 communicates at its bottom and through a channel M with a compartment divided in two parts IE-l 6 by an overflow l1 the height of which is adjusted for establishing an outlet level I8 somewhat lower than the level I9 of the pulp in the reservoir.

This beating engine operates as follows:

The pulp which arrives at one end of the engine at level i9 in the supply reservoir 9 is v`dispensed to the grooves at.l3, under the hydrostatic pressure corresponding to the height of the pulp in the reservoir. On account of its pressure and in spite of the high speed of the rotating cylinder, the pulp fills up the grooves on the cylinder and is drawn away so that its fibers caught between the edges of the blades on the cylinder and the bed-plates 4 are perfectly ground to the required degree according to the pressure which is given to the bed-plates and according to the speed of the cylinder.

As it comes out from the side bed-plates 4, the pulp is projected tangentially upward and thrown down into the reservoir 9 owing to the rounded inner shape of the portion of the vat disposed above the reservoir. The pulp is therefore pulled up to the requiredlevel i9 without any extra expenditure of power.

The pulp travels axially from inlet 8 towards the outlet l"ll passing several times under the cylinder which sends it back to the reservoir. This travelling is necessarily the result of the arrangement of the inlet at one end and of the outlet :at the other end. However in order to adjust the number of times, each pulp unit should pass through the cylinder it is of advantage to provide in the supply reservoir 9 a number of partitions such as (Fig. 2) extending from the lower part of the said reservoir to a convenient height and which will be inclined'downward with advantage inthe direction of the axial path of the pulp so that the pulp projected in reservoir 9 by -a determined section'of the `cylinder may be distributed to the following section of the said cylinder as it drops down tothe bottom of the reservoir,

When'it reaches the other end of thereservoir 9, the pulp follows channel i4, ispoured on the sill -I'I at level I3 and drops down in the outlet conduit I6.

`Should the grinding of the pulp'be not'yet'completed whenit leaves the first -beating'enginea second engine will be arranged in series with the iirst at the same level. In this case some vs'pi'ecial arrangements must be made for giving a suici'ently low level to the pulp inlet of the second engine with respect to the level of the outlet'of the first engine in order to ensure a normal iiow of the pulp. A l

To this end, the vertical outlet conduit I-6 (Fig. l) for the pulp of the irst vbeating eng-ineis replaced (Fig. 3) by a'horizontal outlet 2l, at-level It. The second engine will comprise at the inlet side of its reservoir 9 which is at the'same Ylevel as that of the first engine, a small separate vcompartment 22 (Figs. 2 and 4) in which an inlet 3D connected with the outlet 2| of the rst engine will open at -a level provided for instance at half of the height. This separate compartment -22 is not in communication with' the other comparte ments of the reservoir 9, so that the level of the pulp in said separate compartment 22 is independent of the level of the pulp in the other compartments. The pulp coming into the second engine will I'pass immediately from this separate compartment 22 under the first section of the cylinder and then will be thrown upwardly and ba'ckwardly in the same vertical plane. To prevent the rintroduction-'of said pulp into the separate compartment 22, a vane 23 is arranged above the said compartment, the said Vane being inclined over the cylinder axis and being adjustable by means of a handwheel 24 for guiding the pulp 'into vthe other compartments of the reserv'oir 9. The pulp thus introduced into the other compartments of the reservoir 9 passes from said other compartments under other sections of the cylinder. The pulp being thrown upwardly and abackwardly by said other sections of the cylinder is returned into said other compartments wherein the level of the pulp rises to the high-plane I9 (Fig. l) well above the levelof the pulp in "the separate compartment y22 wherein it is approxrimately in the plane of the inlet 30 (Fig. e). When this second beating Vengine fis connected with a third beating lengine, thepulp ilows "Without the use of special pumping means from the -high outlet y2| (Fig. 3) to the low inlet 30 '(Fig. 4) of the third beating engine 'for 'additional treatment therein in the same fman'ner fas vdescribed above.

The increase in the work llcs't by fri'cztionf-b'e tween the cylinder and beaterplate of lthe engine which is due to the increased cylinder velocity and to the quantity of pulp treated per unit 'of time may lead to some heating of 'the pulp which is prejudicial to the `quality of paper. According to another characteristic fof the invention, the beating engine comprises a cooling device oonstituted'as shown in dotted'lines on'Fig. l'by a'crcula'tion of water between -the double Vwalls 25, 26 provided on the front walls 'l0 and rear walls I of -the'reservoin and also at the ltop "21 of the engine against which the pulpfis-projecte'd as it 4comes lout from'th'e -bed-plates, the saidto'p `in that case being eventually metallic. rIn 'the 'same 'manner the transverse *walls-20 `may be -double and may carryv aco'oling water circulation.

What we claim is:

`1. A'beatin'g engine `for paper pulpinwhichth'e pulp circulates vertically, comprising a closed beater vatfhaving-a-'re'ar Wall, 'fa `front=wall, side walls, an' inlet at one-endo'ftherear wallthereof 'for receiving pulp Iand an outlet 'at-the other endof -therear wallpa beating cylinder in said vat rotatably mountedfonahorizontal shaft yand spaced-'from' the rear wall, a 'bed pla-te in 'ther ront wall 'of-the 'vatfhaving itslast-contact line lwith the cylinder disposed above the horizontaldiar'neter of the cylinder and cooperating4 therewith, a top wall consistingfoffa plane throwingpifp-art inclined upward direction substantially litangential tothefcylinbler along the Asaid lastlcontact line Eand-bf af' curvedv extensionA `of 'said plane throwing off v'part merging "downward into the rear wall; infcombination-with a longitudinalvvall disposed' inthe vat, betweenthe cylinder and the rear wall of thevthaving the' samewidth asthe vat,l extending fromthe I lower portionj `of' the' vat upwardly above the horizontal plane of thesh'aft of the-drum substantialiyto a height equal to from 'about vone to'about yone and *a half times the diameter of the cylinder and Vv"having a *lower cui-ved p'ortioneitending into "'spacebelw the cylinder, said ATetu' Wall and Said longitudinal .g s wall converging towards each other from the top towards the bottom whereby a pulp reservoir is formed within the vat, of markedly decreasing sections from top to bottom, and having a dis charge port at said lower curved portion of the longitudinal wall communicating with space below the cylinder for the discharge of pulp from said reservoir substantially tangentially to said cylinder, said pulp reservoir having an open inlet at its top in the path of pulp freely thrown back.- wardly over the cylinder after its passage through the bed-plate, whereby the pulp is reintroduced into said reservoir for further circulation.

2. A beating engine for paper pulp in which the pulp circulates vertically, comprising a closed beater vat having a rear wall, a front wall, side walls, an inlet at one end of the rear wall thereof for receiving pulp and an outlet at the other end of the rear wall, a beating cylinder in said vat, rotatably mounted on a horizontal shaft and spaced from the rear wall, a bed plate in the front wall of the vat having its last contact line with the cylinder disposed above the horizontal diameter of the cylinder and cooperating therewith, a top wall consisting of a plane throwing off part inclined in upward direction substantially tangential to the cylinder along the said last contact line and of a curved extension of said plane throwing off part merging downward into the rear wall, in combination with a longitudinal wall disposed in the vat, between the cylinder and the rear wall of the vat, having the same width as the vat, extending from the lower portion of the vat upwardly, above the horizontal plane of the shaft of the drum, subM stantially to a height equal to from about one to about one and a half meters and having a lower curved portion extending into space below the cylinder, said rear wall and said longitudinal wall converging towards each other from the top towards the bottom whereby a pulp reservoir is formed within the vat, of markedly decreasing sections from top to bottom, and having a discharge port at said lower curved portion of the longitudinal wall communicating with space below the cylinder for the discharge of pulp from said. reservoir substantially tangentially to said cylinder, said pulp reservoir having an open inlet at its top in the path of pulp freely thrown bachwardly over the cylinder after its passage through the bed-plate, whereby the pulp is reintroduced into said reservoir for further circulation.

3. A beating engine for paper pulp with vertical circulation of the paper pulp, for use in a plant comprising a series of beating engines arranged at the same level and connected with each other by direct pipe lines for supplying pulp from one engine to the next following engine, said beating engine comprising a closed beater vat having a rear wall, a front wall, side walls, an inlet at one end of the rear wall for receiving pulp, and outlet at the other end of the rear wall, a beating cylinder in said vat rotatably mounted on a horizontal shaft and spaced from the rear wall, a bed-plate in the front wall of the vat having its last Contact line with the cylinder disposed above the horizontal diameter of the cylinder and cooperating therewith, a top wall consisting of a plane throwing off part inclined in upward direction substantially tangential to the cylinder along the said last contact line and of a curved extension of said throwing off part merging downward into the rear wall, in combination with a longitudinal wall disposed in the vat, between the cylinder and the rear wall, having substantially the same width as the vat, extending from the lower portion of the vat upwardly above the horizontal plane of the shaft of the drum substantially to a height equal to about the diameter or" the cylinder and having a lower curved portion extending into space below the cylinder, said rear wall and said longitudinal wall converging towards each other from the top towards the bottom whereby a pulp reservoir is formed within the Vat, of markedly decreasing sections from top to bottom, a discharge port at said lower curved portion of the longitudinal wall communicating with space below the cylinder for the discharge of pulp from said reservoir to said cylinder in a substantial tangential direction thereto, said outlet being arranged at a level slightly below the level of the upper edge of said longitudinal, said inlet being arranged at a level below the level of said outlet, a transverse partition disposed in said reservoir, adjacent to one of the side walls of the vat, in the vicinity of the latter, a compartment separated from the remainder of said reservoir and connected with said inlet being formed by said transverse parti* tion in conjunction with said side wall of the vat, the rear wall of the vat and said longitudinal wall, said remainder part of the reservoir being opened at its top, and an adjustable deiiecting vane arranged above said separate compartment and inclined towards said remainder part of the reservoir, said deecting vane and said open top of the'remainder part of the reservoir being in the path of pulp freely thrown backwardly over the cylinder after its passage through the bedplate whereby the pulp is introduced into said remainder part of the reservoir and the pulp in said remainder part of the reservoir may be maintained at a level higher than the level of the pulp in said separate compartment.

EDOUARD HRY. KRISTEN ANDREAS THORSEN.

References Cited in the file of this patent UNITED STATES PATENTS OTHER REFERENCES Ser. No. 366,764, Banning (A. P. 0.), published May 4, 1943.

Randecker, article in Paper Trade Journal, pages 53-55, April 29, 1948. 

